Backyard Aquaponics
A place to discuss aquaponics

I've setup the hardware of my aquaponic system and is ready to start cycling. I'd prefer to cycle without fish since it's a 1200-liter system, so I'm a wary of the risk of losing lots of fish. So that brings me to my options in fishless cycling.

Note: I am not able to source pure ammonia, and I do not wish to use urine. So those options are off the table.

Which option would you recommend?
1) Dead fish
Get some dead fish in the supermarket. Leave it in the tank until ammonia levels rise and the production of nitrates is healthy.

2) Add fishfood, but no fish
Apparently, some aquaponics people in Hong Kong have done this. They've even operated a system without any fish. Just adding fish food pellets and let them dissolve in water.

3) Any other options?

Either way will work.

Dead Fish.... NO

Fish Feed... Perhaps

Other... yeah... FISH... you've got the feed anyway...

It's perfectly safe to cycle with fish... and you don't have to risk "a lot of fish"...

If you start from the perspective of having a.. "1200-liter system, so I'm a wary of the risk of losing lots of fish"...

Then you're probably coming at things from a fish killing perspective anyway...

How many fish you can have.. is entirely determined by your systems ability to process your feed rate...


P.S... another "fishless" alternative... is Urea....

I used Charlie carp fish emulsion to fish less cycle my system. Also handy for feeding conventional beds:-)

dead prawn?

I'll go with the fish food.

Another reason I'm a bit hesitant to use fish is that it's a brand new outdoor system, and I don't think it's that stable in PH. The rain here is quite acid (PH of 5.5), and although I've covered the growbeds with greenhouse plastics and got lids on everything, I'm still not confident that I got it shielded from the elements. While I cycle I'll measure the PH regularly.

Cycling the aquarium can be done with or without fish. Fish-less cycling offers an alternative for the aquarium hobbyist.

So if you were going to supplement a system with fish food how much?

Fish produce solids at a rate of about 4:1 fish:solids.

So by mass only about 25% of what you would feed to fish but you wouldn't be getting the ammonia from the fish so maybe a bit more?